USC’s Matt Barkley and Matt Kalil are keeping it together

Based on how he protects star quarterback Matt Barkley, USC offensive tackle Matt Kalil is a projected first-round NFL draft pick.

So don’t be surprised if the highly touted juniors make similar decisions about their futures in the weeks after Saturday night’s game between No. 10 USC and UCLA at the Coliseum.

Both are weighing whether to turn pro or return to help the Trojans make a run at a Bowl Championship Series title next season.

The Matts will decide separately, but Kalil anticipates a “chain reaction” that will result in the “double package” either moving on or staying put.

“We either both leave or we both stay,” he said recently. “I think that’s the way it will play out.”

Said Barkley: “I think it would be a big factor but not a definite yes or a definite no.”

Kalil’s career has not played out exactly as the former Anaheim Servite High star envisioned when he signed with the Trojans in 2008.

But it’s been close.

Neither he nor his teammates could have predicted that former coach Pete Carroll would leave for the Seattle Seahawks after the 2009 season, or that the NCAA would smack the Trojans with some of the most severe sanctions in college football history.

Through it all, the 6-foot-7 Kalil has emerged as a two-year starter and special teams force — he has blocked four kicks this season — for a team coming off a possible program-turning victory over Oregon.

He and center Khaled Holmes, a fellow fourth-year player, lead a line that was considered the team’s biggest question mark before the season. The Trojans enter their finale against the Bruins having given up only seven sacks, fewer than all but two teams in college football.

“I have a ton of trust and I would say peace of mind knowing he’s got my [blind] side,” Barkley said of Kalil.

Tailback Curtis McNeal also is on the verge of a 1,000-yard season, and it’s no coincidence that his longest gains came on runs over the left side.

Kalil helped stabilize an inexperienced unit by nurturing freshman left guard Marcus Martin.

“You know how hard it is to deal with young bucks — we think we know everything,” Martin said. “But he kind of took me under his wing and treated me like a little brother.”

Kalil, 22, knows what it feels like to be shown the way.

His old brother, Ryan, started at center for the Trojans on national championship teams in 2003 and 2004 and was chosen by the Carolina Panthers in the second round of the 2006 draft. In August, Ryan signed a six-year, $49-million contract, with $28 million reportedly guaranteed.

Now it’s Matt’s turn to cash in.

Or is it?

“I know where I’m at draft-wise, but I also know the other side of it — Matt and I coming back and doing something really special for this university,” he said. “That’s really crossed my mind as something I would want to do.

“But at the same moment, there’s the risk of getting hurt or something like that.”

Kalil had no fear of injury growing up in Corona as the youngest of Frank and Cheryl Kalil’s three children.

While Ryan collected “Star Wars” action figures and cards, Matt favored Evel Knievel-type stunts. He graduated from diving off the top bunk as a youngster to flipping all-terrain vehicles in high school.

“He was the ultimate nerd,” Matt said of Ryan. “I was always the wild guy.”

He also was the tallest.

In fourth grade, school maintenance personnel raised his desk so he would fit. He was 6-2 by eighth grade and grew to 6-5 between his freshman and sophomore seasons at Servite.

“He was like a big baby dog with huge paws, just kind of running into walls,” said Trojans linebacker Chris Galippo, who has been Kalil’s teammate nearly every year since age 8.

But Kalil, with the help of his father and the example set by Ryan, matured into a major prospect.

Frank Kalil played college football at Arkansas and Arizona and professionally in the USFL. He has overseen a youth football program in Corona for more than 20 years.

He is admittedly “old school” when it comes to coaching his boys.

“A lot of people like to play catch,” Frank said, laughing. “I’d say, ‘Hey, let’s not throw the football. Let’s go outside and get in a three-point stance.’”

During Ryan’s tutoring sessions with Frank at a neighborhood park, the father covered footwork, hand position and technique. Matt and Galippo served as blocking sleds.

At first, the younger boys were enthusiastic about imitating their favorite pass rushers.

“You could definitely see their excitement fall from the first couple of Sundays to the next 10 or 12,” Ryan said.

“We’d get destroyed,” Matt said. “We were definitely the body bags.”

Matt watched his older brother dominate higher-rated prospects during a camp at USC and saw him earn a scholarship offer on the spot.

A few years later, then-assistant coach Lane Kiffin phoned Ryan’s larger little brother.

“Hey, what’s up Big Matt?” Kiffin, now the Trojans’ head coach, said during the call. “I want to ask you something. If we offer you a scholarship right now, will you commit?”

“Hell yeah,” Matt said. “I’ll commit.”

Ten minutes later, he recalled, a UCLA assistant was on the phone offering a scholarship.

“I was like, ‘Oh, ‘SC just called and I committed,’” Matt said. “Sorry guys.”

Now, Kalil has another choice to make, for which he will make no apologies.

Stay or go?

“Whatever decision I make will be the right decision for me,” he said. “And I think everyone here will support me, whatever I do.”

gary.klein@latimes.com

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